firing head

1. n. [Perforating]
A mechanical or electronic device used to detonate perforating charges conveyed by tubing, drillpipe, coiled tubing or slickline. This term thus connotes any such device that is not initiated electrically from surface by wireline. A mechanical firing head consists of a percussion detonator that is struck by a firing pin. An electronic firing head is battery powered, to initiate an electric detonator. Electronic firing head systems are used with slickline, coiled tubing and TCP.